The U.S. election process is typically comprised of two components: a nominating contest, in which parties select their standard-bearers, and a general election, in which those party standard-bearers compete for elected office. In the United States, general elections are usually conducted in November of even-numbered years, though some states hold their statewide contests on odd-numbered years.
This paper focuses on the nominating contests held during midterm election cycles. Focusing specifically on midterm election cycles, which tend to see lower voter turnout than during presidential election years, gives researchers the purest view of participation in elections for Congress.
"This study provides strong evidence for the commission’s recommendations to boost primary turnout. States should open up primaries to all eligible voters and move to a single, national primary date or at least consider regionally homogenous dates."
Opening Primaries Up
The Commission on Political Reform recommended states adopt open primaries to allow more eligible voters to participate in the candidate selection process. This analysis shows that states with open primaries do have higher turnout (Figure 7). According to the National Conference of State Legislatures, nine states have completely closed primary systems, in which only registered party members are allowed to vote;2 17 states have either closed or partially closed primary rules, meaning individual parties within each state can restrict participation to only previously registered party members; and an additional eight states only allow unaffiliated voters to participate in the primary of their choice. In the 2018 primary election cycle, only 16 states held fully open forms of primary elections.
The commission recommends states adopt open or semi-open primaries, partly because opening up primaries to independents can increase primary turnout and partly because their presence can help moderate candidates and lead to nominees whose views are more closely aligned with the general public. Previous research has shown that open primaries result in more moderate and representative primary electorates.
In the 2018 primary cycle, states with fully open or “top-two” primaries had an average turnout of 23.9 percent, compared with 19.9 percent for states with semi-open primaries and 18.6 percent for states with closed primaries. Over the past three midterm cycles, states with fully open primaries have averaged turnout of 21.1 percent, versus 17.9 percent for semi-open states and 17.7 percent for closed states (Figure 8). Although primary type did not maintain statistical significance in a multivariate regression, in bivariate analysis states with fully open primary systems did enjoy a statistically significant turnout advantage compared with states with less open systems.
While some party purists argue that only party members should be able to vote in a primary to select their nominees, the reality is that many unaffiliated voters lean strongly toward one side. If a party wants to broaden its reach for the general election, allowing independents to cast ballots in primaries could help with both party building and boosting turnout.
The findings of this analysis of primary turnout rates for the last three midterm federal election cycles are clear: nonpresidential primary turnout remains inadequately low. It is critical that steps be taken to improve turnout. As stated by the Commission on Political Reform in its report Governing in a Polarized America: Encouraging a broader view of participation benefits the parties and the public. Making primary elections more visible to the general public will necessitate a new breed of candidates willing to seek broad support within his or her party…and the electorate as a whole during the general election.
This study provides strong evidence for the commission’s recommendations to boost primary turnout. States should open up primaries to all eligible voters and move to a single, national primary date or at least consider regionally homogenous dates. It also provides initial evidence that a series of additional policies may increase participation: combining primaries for state offices with federal offices, holding primaries during the summer months, allowing voters to cast ballots for uncontested races, and reconsidering nominating conventions that reduce candidate ballot access.
"These steps will lead to a more engaged and involved public and will help strengthen America’s democracy in the years to come."